The conventional, manually adjustable spindle has been used to support motor driven polishing wheels in polishing contact with materials such as glass. While such a spindle can be finely adjusted by its hand wheel so as to position the polishing wheel against the surface of the material to be polished, it will not remain in adjustment as the polishing wheel wears. Thus, to maintain a constant polishing pressure against the material being polished, it has been necessary for the operator to continuously adjust the lifting spindle by operation of the hand wheel. This requires both skill and attention by an operator to achieve a desired result of a uniform polishing.
This invention is directed to a pneumatically adjustable mechanism incorporated into a manually adjustable lifting spindle of a power driven polishing wheel which permits the application of a constant lifting pressure to a polishing wheel throughout a limited distance which will compensate for any wear of the polishing wheel.
An object of this invention is a manually adjustable spindle having a pneumatically applied constant pressure stroke.
Another object of this invention is a manually adjustable spindle to which a constant lifting pressure can be applied across the entire range of mechanical adjustment of the spindle.
A further object of this invention is a mechanically adjustable spindle having a pneumatically applied constant pressure stroke, the length of which stroke can be readily adjusted.
Other objects of the invention may be found in the following specification, claims and drawings.